1. <mathematics> A member of a vector space.
2. <graphics> A line or movement defined by its end points, or by the current position and one other point. See vector graphics.
3. <operating system> A memory location containing the address of some code, often some kind of exception handler or other operating system service. By changing the vector to point to a different piece of code it is possible to modify the behaviour of the operating system.
4. <programming> A one-dimensional array.